Midline corticies were dissected in cold PBS. For ChIP-seq samples, tissue was fixed in ethylene glycolbis (succinimidyl succinate) (EGS) then Formaldehyde; quenched in Glycine, and sonicated to 500bp fragments. Sonicated was immunoprecipitated with appropriate antibody overnight and pulled down with magnetic Dynabeads (Invitrogen). Immunoprecipitated DNA was reverse-crosslinked and purified. NEBNEXT Ultra II DNA Library Prep kit (New England Biolabs) was used to construct multiplex libraries using 5ng of DNA. For RNA-seq RNA was isolated using the RNeasy Plus Mini Kit (Qiagen). RNA libraries were constructed using the Illumina TruSeq RNA Sample Prep Kit with 20ng RNA per sample. Libraries for ChIP-seq and RNA-seq were prepared according to standard Illumina protocols